Triumph Ricardo

The Triumph Ricardo was a British single-cylinder motorcycle made by Triumph Engineering between 1921 and 1928, named after the engine designer Sir Harry Ricardo. It featured an innovative four-valve head, could exceed 70 mph, set three world speed records and won a gold medal in the 1923 International Six Day Trial. Triumph commissioned the 499 cc single-cylinder overhead-valve four-stroke from Ricardo as a replacement for its ageing side-valve engines. The four-valve design, with its valves operated by the existing tappet mechanism, set a new standard for a 500 cc single by making over 20 bhp, the output of a 1500 cc car engine of the time.